Lubricants



" Patented Aug. 21, 1945 LUBRICANTS PATENT OFFICE Elmer Wade Adams, HammomL-ImL, and George W. Flint, Chicago, IlL, assignors to Standard Oil Company, Chicago, 111., a corporation of Indiana i No Drawing.

Application November 2, 1942, Serial No. 464,246

9 Claims. (013252-33) This invention relates to improvements in small arm lubricants and particularly to lubricants especially adapted for the lubrication and protection of small arms of the type ranging from side arms to machine guns.

In our co-pe'nding application, Serial No. 399,674, filed June 25, 1941, which has matured into Patent No. 2,348,715, of which this is, a continuation-in-part, we described therein compositions adapted for the protection of metal sur- 10 faces against corrosion, rusting and/or tarnishing. We describe in said application particular petroleum sulfonates which are the active con stituents of the slushing compositions described.

, We have now discovered that these particular .15

petroleum 'sulfonates when used in combination with certain types of petroleum oils and other addition agents are especially well suited for the lubrication and protection of small size fire arms. Since such materials must be suitable for use under climatic conditions in which wide temperature ranges are encountered they must meets very stringent specifications. In addition to providing the necessary protection against the eleme'nts such materials must be capable of providing adequate lubrication at temperatures in excess of 100 F. as well as at temperatures as low as 60 to -70 F.

We have discovered that lubricants meeting these stringent requirements are obtained by compounding certain mineral oils with particular petroleum sulfonates and certain additives consisting essentially of high molecular weight aliphatic oxygen-containing compounds including a substantial proportion of free saturated aliphatic carboxylic acids.

The petroleum sulfonates employed in the present invention are the soaps 0f sulfonic acids obtained by a particular sulfuric acid treatment of petroleum oils within a definite viscosity range. 40

Heretofore, it had been the generalbelief that the soaps. of preferentially oil-soluble sulfonic acids obtained'by the treatment of petroleum oils with sulfuric acid were of the same type, and therefore were equally effective as inhibitors for the prevention of corrosion and/or-the formation of rust. We have now discovered that contrary to the general belief, there is a marked difference in the corrosion inhibiting properties of soaps of preferentially oil-soluble sulfonic acids obtained from oilsunder various treating conditions. We have discovered that the formation and/or development of tarnish and discoloration upon metal surfaces treated with slushing compounds can be eliminated by employing the soaps of preferen- 0 tion of sodium hydroxide.

tially oil-soluble sulfonic acids derived from a particular sulfuric acid treatment of petroleum oil distillates; namely the soaps of the preferentially oil-soluble sulfonic acids derived by treating distillates of from about 50 seconds to about 1000 seconds or higher, and preferably 200 seconds to 850. seconds to obtain finished oils of from a about 200 seconds to about 400seconds Saybolt Universal viscosity at 100 F. with from about 6 to about 9 pounds, and preferably from about 7 a to about 8 pounds of concentrated sulfuric acid,

preferably fuming sulfuric acid, per gallon of oil.

The method of obtaining these desirable soaps of preferentially oilsoluble sulfonic acids derived from petroleum oils is illustrated by the following example:

The petroleum oil distillate having Saybolt Universal viscosity at 100 F. of from about 200 seconds to about 850 seconds is treated with from about '7 to about 8. pounds of fuming sulfuric acid per gallon of oil in one-half pound increments 1 or dumps. After the acid slud e from each one-half pound acid dump is settled and withdrawn, the next one-half pound of fuming sulfuric acid is added to the oil. The temperature of the oil before the fumin acid'is added thereto is maintained below about F. but due to the heat of reaction upon the addition of the sulfuric acid, the temperature of the oil may rise to from about F. to about F. After the required total amount of fuming sulfuric acid has been added to the oil and the oil freed of acid sludge, the acid treated oil containing oil-soluble sulfonic aids dissolved therein, is neutralized with a solu- The aqueous alkali solution isthen separated from the oil solution containing dissolved therein sodium soap of sulfonic acids and the latter then separated from the oil by extraction with alcohol of about 60%- strength. "The alcohol layer containing dissolved sodium sulfonates is then separated from the oil,

and subsequently distilled to recouer the alcohol and remove water. The sulfonic soap obtained inthis manner contains from about 30% to about 60% sodium sulfonate, from about 30% to about 60% oil; from about 1% to about 10% water, and

up to. 10% of inorganic salts which may be removed by the procedure hereinafter described.

The oil containing dissolved sulfonic acids is extracted with about 60% alcohol to remove the sulfonic acids which may then beneutralized with sodium hydroxide and subsequently freed Of the alcohol by distillation.

' times. approximately 1 x4 inches are coated with the The crude soaps of these preferentially oil-' soluble sulfonic acids obtained by the procedure described above may befreed of inorganic salts by purification. This purification is preferably accomplished by dilution of the crude soap with from about /2 to about 10 parts, preferably 1 to 2 parts of 50% or higher strength alcohol, preferably alcohol of 60 to 70% strength, and allowing the salts to settle while maintaining the mixture within the temperature range of 130 to 175 F., preferably 155 to 165 F. When the salts have settled the supernatant alcohol-soap layer is separated and the alcohol isrecovered by con- 4 ventional distillation procedure. I

The soaps of these preferentially oil-soluble sulfonic acids obtained in the manner above described differ from other oil-soluble soaps of sulfonic acids from'other fractions such as for example,.those obtained by treating petroleum distillates of from about 50 seconds to about 150 seconds Saybolt Universal viscosity at 100 F. with from about 3 pounds to about 4 pounds of fuming sulfuric acid per gallon of oil, and the ter, although they do shown some hydroscopic tendencies.

top of the humidity cabinet. To insure that only moisture of condensation comes in contact with the strips, stainless steel shields are placed above the strips in such a position that no moisture from the shields can drip on the strips. The following petroleum, sulfonates were tested under the foregoing conditions: I

Sulfonate I. -Sulfonates obtained from distillates of 200-850 seconds Saybolt Universal viscosity at 100 F. treated with from about 7 to about 8. pounds of fuming sulfuric acid per gallon of distillate, and neutralized with sodium hydroxide. The sulfonate so obtained is that employed inaccordance with the present invention.

Sulfonate II.-Sulfonates obtained from distillates of from about 50 to about 150 seconds Saybolt Universal viscosity at 100 F. by treating with from 3 to 3 /2 pounds of fuming sulfuric acid per gallon of distillate, and neutralizing with sodium hydroxide;

SuZ onate III.-Sulfonates obtained from distillates of about 80 seconds to about 150 seconds Saybolt Universal viscosity at 100 F. by treating with pounds of fuming sulfuric acid per gallon of distillate, and neutralizing with sodium hydroxide.

sulfonates II and III are the type of sulfonates heretofore used in slushingcompounds. These were found to cause tarnish and discoloration of metal surfaces.

The results obtained in the humidity cabinet tests on naphtha solutions of the foregoing type of petroleum sulfonates are shown in the following table. I

TABLE I sulfonates. in naphtha solution Analysis of sodium sulfonate Dura- Petroleum sodi- Percent tion Condition um sulionate soap 0! test, of strips Percent Percent Percent Percent used days soap oil salt H 34. 2 58.8 4. 8 6.0 10 2' No tarnish. 1 3 D0. 5 Do. Dry 30 3 Do.

46.9 46.2 1.3 1.0 1o 2 giff fi f m 2 Severe rust. H 'slarnish. t evere IDS 2 ramish.

evere rust. Tarnish. m 45.1 4&0 1.34 1.4 so 2 gjg The eflectiveness of the particular petroleum sulfonates used in the present invention in preventing discoloration and/or tarnish. of metal surfaces on which it is applied is demonstrated by accelerated tests carried out in a-humidity cabinet wherein intermittent periods of heating and cooling are employed while maintaining saturated air conditions within the cabinet. The humidity cabinet which is provided with heating units and thermal regulators for automatic temperature control is maintained on a cycle of 20 hours cooling at 40-45" F. and four hours heating at 100 to 105 F. A water level of 2-3 inches is maintained in the. bottom of the cabinet to give approximately saturated conditions at all Cold-rolled open hearth steel strips of rust preventive material and suspended by glass h a glass rod running across the The foregoing data clearly demonstrate the tarnish forming tendencies of sodium sulfonates II and III and the absence of any tendency of sulfonate I to form tarnish.

Depending upon the severity of the conditions I under which the various grades of slushing compounds are to be employed from about 1% to about 40% of the petroleum sulfonates of the present invention are employed in the slushing compounds.- While we prefer to employ thesodium soap of such sulfonic acids, other soaps of metals of groups I, II, IV, VI, and VIII of the periodic table may be employed. Thus, for example, we may employ the potassium, calcium,

barium, tin, lead, aluminum, chromium, cobalt,

' and nickel soaps of the sulfonic acids obtained by treating petroleum distillates of from about 50 to about 1000 seconds or higher, and preferably from about 200 seconds to about 850 seconds Say- 'aaeaoas Q 3 3 'bolt Universal viscosity at 100 F.'with from about 6 to about 9, and preferably from about 7 to about 8 pounds of fuming sulfuric acid per gallon of distillate.

In accordance with the present invention a. petroleum sulfonate of the foregoing type is mixed with a petroleum oil having aSaybolt Universal viscosity at 100 F. withinthe range of from about 45 seconds to about 70 seconds and a pour test of from about -40 F. to about 70 F.

In addition to the particular type petroleum sulfonate and oil our improvedlubricant contains in addition small amounts of a compound which comprises a mixture of aliphatic oxygen-containing compounds of petroleum origin obtained by 1 controlled oxidation of hydrocarbons or mixtures thereof, such as the hydrocarbons occurring in r or associated with petroleum oils, in liquid phase under the trade name of "Alox compounds; com-v pounds marketed as -Alox 152, Alex 350 and 'iA-IOX 600 are-well suited for this purpose. For the purpose of identifyingthese compounds they will be referred to hereinafter in this specification and the appended claims as petroleum oxidation products."

For the purpose of lubricating and protecting fire arms of the type described composition falling within the following approximate ranges can beemployed:

Per cent ,Mineral oil 70-90 Sodium sulfonate"(oil free) 2-10 Petroleum oxidation products" -6 seconds to about 850 seconds S aybolt Universal viscosity at 100 F. with 78 pounds of fuming sulfuric acid and neutralizing the sodium hydroxide.

The "petroleum oxidation products which we have found well suited for main the above compositions are products marketed as "Alex 152,"

Alex 600 and Alox 350." These may be used in amounts ranging from 0.5% to 6.0% respeow tively or collectively in the finished oil.

A product which has been found particularly well suited for the lubrication and protection of small fire arms'is one having the following approximate componsition:

I Per cent Mineral oil 82 Olly-containing sodium sulfonate (oil-free approximately .t 14

Petroleum oxidation product 4 1 Saybolt Universal viscosity at 100 F. 50-55 seconds. pour point about 60 F.

2 Obtained by treating distillates of from about 200 seconds to about 850 seconds Saybolt Universal viscosity at 100: F. with 7-8 pounds of fuming sulfuric acid and neutralizing the sodium hydroxide.

F Preferably the product marketed as "A101: 600 or the product gnarketed as 113x152.

Another effective composition is one havingap- ,-proximately ,the same compositions as the above except'.-tliati, the fpetroleum oxidation product is a blend of 2% of the product marketed as Alox 600 and 2% of the product marketed as Alox 350.

Still another effective composition is one having approximately the following composition:

I Percent Mineral oil 88-94;

Sodium sulfonate (oil free) 6.0-12

.Saybolt Universal viscosity at 100 F. approximatel 45-49 Fseconds; pour point approximately -40 E.-

Obtained by treating distillates of from about 200 seconds to' about 850 seconds Saybolt Universal viscosity at 100 F. with 7-8 pounds of fuming sulfuric acid and neu- 5 tralizing the sodium hydroxide.

Products of the foregoing compositions have been found to effectively lubricate small size fire arms at temperatures as low'as -70? F. and have provided complete corrosion protection for a pcriod of 200 hours in an atmosphere maintained at 100 F. and 100% humidity.

While we have described the present invention in connection with the lubrication and protection of fire arms it is to be understood that the same is not limited thereto. Obviously our improved products are equally well adapted for the lubrication and protection of other metal articles, such as highly finished metal articles, for example; fishing reels, cutlery, sewing machines, and

3b the like.

Although we have described the invention in connection with certain specific embodiments thereof it is understood that these are by way of illustration only and not by way of limitation.

We claim: x

l; A composition of matter comprising a major proportion of a mineral oil having a Saybolt Universal viscosity at 100 F. within the range of about 45 seconds to about 70 seconds, from 40 about 1% to about 40% of a. soap of preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having a. Saybolt Universal viscosity at 100 F. within the range of about 50 seconds to about 1000 seeonds with from about 6 pounds to about 9 pounds 1 Saybolt Universal viscosity at 100 F. -55 seconds pour point about F.

Obtained by treating distiilates of from about 200 of concentrated sulfuric acid per gallon'of distillate, and from about 0.5% to about 6% of a mixture of saturated aliphatic oxygen-containing compounds including alkyl ester, lactones, ketones, alcohols and al-cohol-ketones, said saturated aliphatic oxygen-containing compounds being obtained by the partial oxidation of petroleum hydrocarbons.

2. A composition of matter comprising a major 5 proportion of a mineral oil having a Saybolt Universal viscosity at 100 F. of from about 45 seconds to about '70 seconds anda pour point of at least about -40 F., from about 1% to about 40% of a. metal soap of preferentially oil- 0 soluble sulfonic acids obtained by treating a petroleum distillate having a baybolt Universal viscosity at 100 F. of from about.50 seconds to about 1000 seconds with from about '6 pounds to about 9 pounds of concentrated fuming sulfuric acid per 'gallon of distillate, and from about 0.5% to about 6% of a mixture of sat-' urated aliphatic oxygen-containing compounds including alkyl esters, lactones, ketones, alcohols and alcohol-ketones; obtained by the partial oxi- 7 dation of petroleum hydrocarbons.

3. A composition of matter as described in I claim 2 in which the metal soap is sodium soap. 4. A composition of matter as described in claim 2 in which the metal soap is calcium soap;

5.'A composition of matter as described in claim 2 in which the metal soap is aluminum soap.

6. A mineral oil' composition having a pour point of at least about --i F. and-adapted for the lubrication and protection of metal articles comprising a major proportion of a petroleum oil having a Saybolt Universal viscosity at 100 F. of from about 45 seconds to about 70 seconds and a pour point of at least about --4,0 F., from about 1% to about 40% of analkali metal soap of preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having a Saybolt Universal viscosity at 100 F. of from about 200seconds-to about 850 seconds with from about 7 to about 8 pounds of fuming sulfuric acid per gallon of distillate, and from about 0.5% to about 6% of a mixture of saturated aliphatic oxygen-containing compounds including alkyl esters, lactones, ketones and alcohols, said oxygen-containing compounds being obtained by the partial oxidation Of petrolemn hydrocarbons.

7. A composition of matter comprising about 70% to about 90% mineral oil having a Saybolt Universal viscosity at 100 F; within the range of about 45 seconds to about 70 seconds, about 2% to 10% of a soap of preferentially oil-soluble sul- 70% to 90% or a mineral oil having a Saybolt Universal viscosity at 100 F. of from about 45 secondsto about 70 seconds and a pour point of at least about 40 F., about -'2% tol0% of a metal soap of preferentiallyv-oil-soluble suli'onic acids obtained by treating a petroleum distillate having a Saybolt Umversail if cosity at 100 F.

of from about 50 seconds" to. about 1000 seconds with from about 6, pounds to about 9 pounds of concentrated fuming sulfuric acid. per gallon of distillate, and about 0.5% to 6% of a mixtur of saturated aliphatic oxygen-containing compounds including -aikyl .esters, lactones, ketones, I alcohols and alcohol-ketones, obtained by the\ partial oxidation of petroleum hydrocarbons.

9, A fire-arm lubricant and coating composition adapted for service at temperatures as low as at least 40 F. comprising about 70% to 90% of a mineral oil having a SayboltUniversal vis-- ionic acids obtained by treating a petroleum distillate-having a Saybolt Universal viscosity at,

100 F. within the range of about 50 seconds to about 1000 secondswith from about 6 pounds to about 9 pounds of concentrated sulfuric acid per gallon of distillate, and about 0.5% to 6% of a mixture of saturated aliphatic oxygen-containing compounds obtained by the partial oxidation of petroleum hydrocarbons.

8. A composition of matter comprising about cosity at 100 F. of from about: seconds to about seconds and a pour point ofat least about -40 Fl, about 2% .to 10% of an'alk'aii metal soap of preferentially:oil-soluble sulfonic acids obtained by treating a petroleum distillate having a SayboltJJniversalviscosity at F. of

-from'about 50 seconds to about 1000 seconds with ELMER WADE ADAMS. GEORGE W. FLINT. 

